Climatic and social changes influence the distribution and the dynamics of mosquito-borne diseases thus contributing to the risk of emergence and resurgence of epidemics (malaria, dengue, chikungunya). For most mosquito-borne diseases, there is to date no vaccine and no curative treatment. The vector control and the prevention of mosquito bites are particularly based on the safe and efficacious use of chemicals. Because mosquitoes become resistant, it is essential to develop new strategies against insects to increase treatment efficacy and to circumvent resistance mechanisms.
Chemicals which have been classically used up to now are classified into two main categories, according to their mode of action: in the first category are insect repellent molecules which prevent mosquitoes of approaching their target and in the second category are insecticide molecules which “kill” the mosquitoes.
In the repellent molecules category, the broadly used insect repellent in the world is DEET (N,N-diethyl-3-methylbenzamide, previously named N,N-diethyl-m-toluamide). Other known insect repellents are Icaridin (KBR) and IR3535® (3-[N-Butyl-N-acetyl]-aminopropionic acid, ethyl ester). To be effective against most mosquitoes implies that they have to be usually employed at relatively high concentrations in the compositions to be applied for instance on clothes or nets. However a compromise should be found between efficacy and adverse effects.
Insecticide synthetic molecules which are widespread used against mosquitoes, are chosen in the pyrethroid, carbamate or organophosphate families. However mosquitoes have become more and more resistant to these chemicals, in particular to the pyrethroid insecticides which have been widely used for house spraying and impregnation of mosquito nets for instance for malaria control. New insecticide candidates are thus searched for.
Recent studies (Bonnet J. et al. (2009) Multi-function oxidases are responsible for the synergistic interactions occurring between repellents and insecticides in mosquitoes. Parasites & Vectors 2:17) have described the efficiency of the combination of a non-pyrethroid insecticide (propoxur from the carbamate family) with a repellent (DEET) against the main dengue vector mosquito Aedes aegypti. 
A first aim of the invention is to provide a new composition which can be used in the control of pyrethroid resistant mosquitoes.
Another aim of the invention is to provide a composition which can help controlling the mosquito-borne diseases such as malaria, dengue and chikungunya.
Another aim of the invention is to provide an insecticide composition having an optimized insecticide treatment efficacy while reducing doses.